Interlock system for multi-door enclosures

ABSTRACT

A multi-door enclosure includes an enclosure body, a primary door having an actuator and a secondary door. An interlock member having a holding section extends between the primary door and the secondary door. As the primary door closes, the actuator contacts the interlock member to translate the interlock member towards the secondary door until the holding section engages the secondary door.

FIELD OF THE INVENTION

This invention relates to the field of electrical enclosures, and morespecifically to a method and apparatus for interlocking the doors of amulti-door enclosure.

BACKGROUND

Electrical enclosures can be used to house assorted electricalequipment. The enclosure protects the electrical equipment from theenvironment and helps prevent access to the equipment. Multi-doorenclosures are enclosures with two or more doors. Multi-door enclosuresinclude a primary or master door and one or more secondary or slavedoors. In some applications, industry standards require that thesecondary doors be unopenable unless the primary door is opened. Toperform such a function, some multi-door enclosures include relativelycomplex and large mechanisms which disable the door handle latchmechanism of the secondary door when the primary door is closed andenable the handle latch mechanism of the secondary door when the primarydoor is open. A smaller and less complex system is needed for multi-doorenclosures.

SUMMARY

In one aspect a multi-door enclosure includes an enclosure body, aprimary door having an actuator and a secondary door. An interlockmember having a holding section extends between the primary door and thesecondary door. As the primary door closes, the actuator contacts theinterlock member to translate the interlock member towards the secondarydoor until the holding section engages the secondary door to prevent thesecondary door from being opened.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a perspective view of a multi-door enclosure according toone embodiment.

FIG. 1B shows an exploded view of a door latch assembly of the enclosureof FIG. 1A.

FIG. 2 shows a perspective view of an interlock member according to oneembodiment.

FIG. 3 shows a back view of the interlock member of FIG. 2.

FIG. 4 shows a perspective view of an interlock assembly according toone embodiment.

FIG. 5A shows a perspective view of a latch assembly of the interlockassembly of FIG. 4.

FIG. 5B shows a perspective view of a latch assembly according to oneembodiment.

FIG. 6A shows a perspective view of a multi-door enclosure according toone embodiment.

FIG. 6B shows an embodiment of an interlock assembly for the enclosureof FIG. 6A.

FIG. 7A shows a perspective view of a multi-door enclosure according toone embodiment.

FIG. 7B shows an embodiment of an interlock assembly for the enclosureof FIG. 7A.

FIG. 8A shows a perspective view of a multi-door enclosure according toone embodiment.

FIG. 8B shows an embodiment of an interlock assembly for the enclosureof FIG. 8A.

FIG. 9 shows a perspective view of an interlock member according to oneembodiment.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings which form a part hereof, and in which is shown byway of illustration specific embodiments in which the invention may bepracticed. These embodiments are described in sufficient detail toenable those skilled in the art to practice the invention, and it is tobe understood that other embodiments may be utilized and that structuralchanges may be made without departing from the scope of the presentinvention. Therefore, the following detailed description is not to betaken in a limiting sense, and the scope of the present invention isdefined by the appended claims and their equivalents.

FIGS. 1A-1B show a multi-door enclosure 100 according to one embodiment.Enclosure 100 includes an enclosure body or housing 110 having a primarydoor 112 and a secondary door 114. Enclosure 100 is for holdingelectrical equipment. Doors 112 and 114 are attached to housing 110 byhinges 116 and 118 respectively. Each door 112 and 114 includes aconventional door latching assembly 120. Referring to FIG. 1B, doorlatching assembly 120 is actuated by turning a handle 121 which in turnrotates a latch 122 which engages side flange 124 of housing 100. A pairof vertically translating members 126 and 128 are also actuated byhandle 121 and translate to engage top and bottom portions 130 and 132,respectively, of housing 100.

Enclosure 100 is designed such that secondary door 114 cannot be openedunless primary door 112 is open. In other words, if primary door 112 isclosed, secondary door 114 will be unopenable.

In one embodiment, enclosure 100 includes an interlock assembly 140which is configured to prevent secondary door 114 from being openedunless primary door 112 is opened first. In one embodiment, interlockassembly 140 includes an actuating member 142, an interlock member 146,and a latch assembly 148. Interlock member 146 extends between primarydoor 112 and secondary door 114 and includes a holding section 150. Inthis example, interlock member 146 is slidably coupled to an upperportion of enclosure 100 and extends horizontally between door 112 anddoor 114. As primary door 112 closes, actuator 142 contacts one end ofinterlock member 146 to translate interlock member 146 horizontallytowards secondary door 114 until holding section 150 engages latchassembly 148 on secondary door 114. This prevents secondary door 114from being opened.

Actuator 142 can include a rigid, planar plate structure extendinggenerally perpendicularly from the inside surface of primary door 112.In one embodiment, actuator 142 can be proximate a hinged side ofprimary door 112.

FIG. 2 shows further details of interlock member 146, in accordance withone embodiment. Interlock member 146 is mounted to housing 110 by one ormore fasteners 202, for example. Interlock member 146 includes anelongate rigid main body portion 204, formed of steel or aluminum forexample, which extends from a first end 205 to a second end 206. A pairof slots 208 and 210 extend longitudinally along portions of the firstand second ends, respectively, of the interlock member. Fasteners 202mount the interlock member to the housing such that the interlock memberslides freely back and forth relative to housing 110 via slots 208 and210. In one embodiment, nylon washers 203 can be provided to decreasefriction.

In one embodiment, interlock member 146 includes a roller bearing 212 onfirst end 205. Roller bearing 212 is contacted by actuator 142 (FIG. 1)when the primary door is closing to cause interlock member to translatetowards the secondary door. In one embodiment, interlock member 146includes holding section 150 on second end 206. In this example, holdingsection 150 includes a U-shaped projection 216 extending from main body204. A lower projecting section 220 is adapted to engage latch assembly148 (FIG. 1) when the primary door is closed and interlock member 146has been translated towards the secondary door. This holds the secondarydoor closed and the secondary door cannot be opened until the interlockmember moves back towards the primary door.

FIG. 3 shows an inside, back view of interlock member 146 mounted toenclosure housing 110. Interlock member 146 fits within a very smallspace 305 at the upper portion of the housing. This small footprintheight-wise allows for the interlock assembly to be used in low-profileenclosures. For example, in one embodiment space 305 has a height ofapproximately 1⅜ inches. In one embodiment, a biasing member such as aspring 306 is mounted between fastener 202 and second end 206 ofinterlock member 146. Spring 306 provides a force to bias the interlockmember back towards the primary door to automatically un-latch thesecondary door from holding section 150 when the primary door is opened.Then, as the primary door is closed, the actuator on the primary doorcontacts bearing 212 to move the interlock towards the secondary door,where holding section 150 then engages the secondary door. When theprimary door is opened, spring 306 forces or biases the interlock memberback towards the primary door.

FIG. 4 shows further details of the interaction between actuating member142, interlock member 146, holding section 150, and latch assembly 148.Actuator 142 holds interlock member 146 so that holding section 150 islatched to latch assembly 148. When primary door 112 is rotated open,actuator 142 also moves away from interlock member 146. Spring 306 pullsthe interlock member, via slots 208 and 210 towards the primary door sothat holding section 150 no longer engages latch assembly 148. Thisallows the secondary door to be opened. In some embodiments, latchassembly 148 can be located on interlock member 146 and holding section150 can be located on the secondary door 114.

FIG. 5A shows details of latch assembly 148, according to oneembodiment. Latch assembly 148 includes a body 501 including a mountingportion 502 to mount the latch assembly to the secondary door of theenclosure. A section 504 perpendicularly extends from mounting portion502. Latch member 506 is rotatably coupled to section 504. In oneembodiment, latch member 506 includes an upper latching portion 508 anda lower, weighted portion 510. A projection 512 keeps latch member fromrotating any further counterclockwise (relative to FIG. 5A) thanvertical. Holding section 150 (FIG. 4) engages upper latching portion508. Upper surface 514 of upper portion 508 includes a camming surface.This allows the secondary door to be closed and latched if the primarydoor is closed first. For example, if the primary door is closed andinterlock member 146 (FIG. 4) has been translated over towards thesecondary door, then camming surface 514 will contact holding section150 as the secondary door is being closed. This will rotate latch memberclockwise (relative to FIG. 5A) and latch member 506 will slide underholding section 150. Once camming surface 514 has passed the holdingsection, weighted portion 510 will rotate the latch membercounterclockwise to a vertical position where the latch member 506 willthen be held by holding section 150, and thus not allowing the secondarydoor to be opened.

Some embodiments can use a spring or other biasing member in place of,or in addition to, weighted portion 510 to bias the latch member 506 toa vertical orientation. For example, FIG. 5B shows a latch assembly 148Bwith a biasing member, such as a spring 509, to bias a latch member506B.

The present system can be adapted to be used for three, four or moredoor multi-door enclosures.

FIG. 6A shows a three door multi-door enclosure 600, in accordance withone embodiment. Enclosure 600 includes a housing 610 having three doors612, 614, and 616 hingedly connected to a front of the housing. Door 612is a primary door and includes an actuating member 142, as discussedabove. Secondary doors 614 and 616 each include latch assembly 148mounted to an inner surface of the doors. Enclosure 600 includes aninterlock assembly which includes an interlock member 646 which extendsbetween primary door 612, across secondary door 614, and to secondarydoor 616.

FIG. 6B shows further details of interlock member 646, according to oneembodiment. Interlock member 646 includes a first interlock member 146as discussed above. A second interlock member 652 is coupled tointerlock member 146 by a rigid coupling shaft 650. Interlock member146, coupling shaft 650 and second interlock member 652, in combination,form the interlock member 646 for a three door enclosure. Secondinterlock member 652 includes an elongate, rigid body 658 slidablymountable to housing 610 in a similar manner as interlock member 146,discussed above. Second interlock member 652 includes a slot 656 on oneend for coupling to coupling shaft 650. In this example, a pair of bolts654 are located on either side of slot 656 to hold the coupling shaftwithin slot 656. Second interlock member 652 includes a pair of holdingsections 660 and 662 proximate the respective ends of the interlockmember 652. Holding sections 660, 662 engage latch members 148 in themanner described above.

FIGS. 7A and 7B show a four door enclosure 700 according to oneembodiment. Enclosure 700 includes a housing 710 and four doors 712,714, 716, and 718, similar to the doors described above. Primary door712 includes an actuator 142 coupled to an upper portion of the insideof the door and positioned proximate the hinged side of door 712.Actuator 142 contacts an interlock member 746 which translateshorizontally towards the secondary doors 714, 716, and 718 to engagelatch members 148 located on an upper portion of those doors. Referringto FIG. 7B, in this example, interlock member 746 includes a firstinterlock member 146 and a second interlock member 652 coupled by anelongate, rigid coupling shaft 750. Holding sections or members 150,660, and 662 engage the latch assemblies 148 of the secondary doors.

FIGS. 8A and 8B show a five door enclosure 800 according to oneembodiment. Enclosure 800 includes a housing 810 and five doors 812,814, 816, 818, and 820, similar to the doors described above. Primarydoor 812 includes an actuator 142 coupled to an upper portion of theinside of the door and positioned proximate the hinged side of door 812.Actuator 142 contacts an interlock member 846 which translateshorizontally towards the secondary doors 814, 816, 818, and 820 toengage latch members 148 located on an upper portion of those doors.Referring to FIG. 8B, in this example, interlock member 846 includes afirst interlock member 146 coupled by a rigid coupling shaft 850 to asecond interlock member 652 which is coupled by an elongate, rigidcoupling shaft 852 to a third interlock member 652B.

FIG. 9 shows a perspective view of an interlock member 946, inaccordance with one embodiment. Interlock member 946 performs ingenerally the same manner as interlock member 146 (FIG. 2), discussedabove, and the above discussion is incorporated herein. Interlock member946 is mounted to enclosure housing, such as housing 110, discussedabove. A holding section 950 on an end of the interlock member isadapted to engage a latch assembly 948 mounted to a secondary door ofthe enclosure.

In this embodiment, holding section 950 includes an upper section 952mounted to the interlock member body and a lower section 954 which isrotatably attached to upper section 952. Holding section 950 is designedlike a hinge in that the lower section 954 can swing inward but cannotswing outward. Thus, as the secondary door is closing, a lip 956 onlatch assembly 948 rotates lower section 954 upward until lip 956 passesand then lower section 954 falls into a cut-out 958 of the latchassembly 948. Someone trying to open the secondary door would then notbe able to since the lower section 954 cannot rotate outward. To openthe secondary door, the interlock member 946 is translated away from thesecondary door, as discussed above, and holding section 950 moves out ofcut-out 958. The example interlock member of FIG. 9 can be used in placeof, or in addition, to any of the embodiments discussed above.

Thus, using only a few simple members, the present system provides aninterlock assembly and system which can be used for many different sizemulti-door enclosures. In some embodiments, by latching the interlockmember directly to the secondary door, instead of trying to control thehandle latch mechanism of the secondary door, a slim, easy tomanufacture and easy to assemble interlock design is provided. In someembodiments, by utilizing a horizontally translating interlock member,the present interlock assembly can fit within small, low-profileenclosures.

It is understood that the above description is intended to beillustrative, and not restrictive. Many other embodiments will beapparent to those of skill in the art upon reviewing the abovedescription. The scope of the invention should, therefore, be determinedwith reference to the appended claims, along with the full scope ofequivalents to which such claims are entitled.

1. A multi-door enclosure comprising: an enclosure housing; a primarydoor attached to the enclosure housing and having an actuator; asecondary door attached to the enclosure housing; and an interlockmember extending between the primary door and the secondary door, theinterlock member including a holding section; wherein, as the primarydoor closes, the actuator contacts the interlock member to translate theinterlock member towards the secondary door until the holding sectionengages the secondary door to prevent the secondary door from beingopened.
 2. The multi-door enclosure of claim 1, wherein the actuator islocated proximate a hinged side of the primary door.
 3. The multi-doorenclosure of claim 1, wherein the actuator includes a rigid plateextending from an inner surface of the primary door and positioned so asto contact an end of the interlock member when the primary door isclosed.
 4. The multi-door enclosure of claim 1, wherein the interlockmember is translatable in a horizontal direction between the primarydoor and the secondary door.
 5. The multi-door enclosure of claim 1,wherein a biasing member is coupled to the interlock member to bias theinterlock member towards the primary door when the primary door isopened.
 6. The multi-door enclosure of claim 1, wherein the secondarydoor includes a latch assembly to engage the holding section of theinterlock member.
 7. The multi-door enclosure of claim 6, wherein thelatch assembly includes a body mounted to the secondary door and a latchmember rotatably coupled to the body.
 8. The multi-door enclosure ofclaim 6, wherein the latch assembly includes a cut-out section to engagea rotatable lower section of the holding section.
 9. The multi-doorenclosure of claim 1, wherein the multi-door enclosure includes a secondsecondary door and the interlock member includes a second holdingportion which engages the second secondary door when the primary doortranslates the interlock member towards the second secondary door. 10.An interlock assembly for a multi-door enclosure having a primary doorand a secondary door, the interlock assembly comprising: an interlockmember horizontally movable between the primary door and the secondarydoor; an actuating member coupled to the primary door to translate theinterlock member towards the secondary door as the primary door is beingclosed; and a member on the secondary door which engages a portion ofthe interlock member when the primary door is closed such that thesecondary door cannot be opened.
 11. The interlock assembly of claim 10,wherein the interlock member includes a first end having roller bearingto contact the actuating member.
 12. The interlock assembly of claim 10,wherein the actuating member includes a rigid plate extending from aninner surface of the primary door and positioned so as to contact an endof the interlock member when the primary door is closed.
 13. Theinterlock assembly of claim 10, wherein a biasing member is coupled tothe interlock member to bias the interlock member towards the primarydoor when the primary door is opened.
 14. The interlock assembly ofclaim 10, wherein the secondary door includes a latch assembly to engagethe holding section of the interlock member.
 15. The interlock assemblyof claim 14, wherein the latch assembly includes a body mounted to thesecondary door and a latch member rotatably coupled to the body.
 16. Theinterlock assembly of claim 14, wherein the latch assembly includes acut-out section to engage a rotatable lower section of the holdingsection.
 17. A multi-door enclosure comprising: an enclosure housing; aprimary door hingedly attached to the enclosure body and having anactuator located proximate an upper portion of the primary door; asecondary door hingedly attached to the enclosure body and having alatch assembly located proximate an upper portion of the secondary door;and an interlock member extending between the primary door and thesecondary door and horizontally translatable between the primary doorand the secondary door, the interlock member having a biasing memberattached to the interlock member to bias the interlock member towardsthe primary door, wherein the interlock member includes a first endwhich is contacted by the actuating member when the primary door isclosed causing the interlock member to translate towards the secondarydoor, the interlock member including a second end having a holdingsection which engages the latch assembly of the secondary door when theprimary door is closed such that the secondary door cannot be openedwhen the primary door is closed.
 18. The multi-door enclosure of claim17, wherein the latch assembly includes a body mounted to the secondarydoor and a latch member rotatably coupled to the body.
 19. Themulti-door enclosure of claim 17, wherein the multi-door enclosureincludes a second secondary door and the interlock member includes asecond holding portion which engages the second secondary door when theprimary door translates the interlock member towards the secondsecondary door.
 20. A method of interlocking a multi-door enclosure, themethod including: translating an interlock member from a primary doortowards a secondary door by closing the primary door; and latching thesecondary door to a portion of the interlock member.
 21. The method ofclaim 20, wherein translating includes horizontally moving the interlockmember.
 22. The method of claim 20, wherein translating includescontacting an end of the interlock member with an actuating memberextending from an inner surface of the primary door.